A wireless device (e.g., a cellular phone or a smartphone) in a wireless communication system may transmit and receive data for two-way communication. The wireless device may include a transmitter for data transmission and a receiver for data reception. For data transmission, the transmitter may modulate a radio frequency (RF) carrier signal with data to generate a modulated RF signal, amplify the modulated RF signal to generate a transmit RF signal having the proper output power level, and transmit the transmit RF signal via an antenna to a base station. For data reception, the receiver may obtain a received RF signal via the antenna and may amplify and process the received RF signal to recover data sent by the base station.
The wireless device may include one or more amplifiers to process analog communication signals. Some wireless devices may operate within multiple frequency bands. For example, the wireless device may transmit a wireless signal within a first frequency band or within a second frequency band. Such wireless devices may include two or more amplifiers that may be optimized to transmit the wireless signal within each of the first frequency band or the second frequency band.
Coupling signals between processing stages and the amplifiers of the wireless device may provide design challenges, especially when the first frequency band is much greater (e.g., faster) than the second frequency band. For example, coupling communication signals in widely varying frequency bands may be difficult because of frequency dependent loading effects that may be associated with some signal pathways of the wireless device. These frequency dependent effects may adversely affect amplifier gain.
Thus, there is a need to effectively couple communication signals to amplifiers within multiple frequency bands to mitigate frequency dependent effects.